Piston for internal-combustion engines



May l2, 1953 w. Hl-:UssER PIsToN FOR INTERNAL-COMBUSTION ENGINES FiledI Fb. 13, 195o 2 Sheets-Sheet 1 F/Gf 2.

zal am.,

mnemor: /fr/a' Heusser, ,www

Gttornegs.

May kl2, 1953 w. HEUssER PIsToN FOR INTERNAL-COMBUSTION ENGINES 2 Sheets-Sheet 2 Filed Feb. l5, 1950 me n w E. i a z 5 .w E I 5 z w E. H m T W E SN/NAVE R, w M a a m5 W PII u IJY 4 4 0 4 il WM, @103| 4 V A r A@ d# W 4 Q /\\\0 Q 7- w w r www F( M wf, C 2J A l M6 .l 4 bu. .i 4a7 a a, .n/ 14. /r* a rwtfN Patented May 12, 1953 y 2,633,391 Pis'roN Foa INTERNAL-COMBUSTION ENGINES Wilfrid Heusser, sait Lake city, Utah Application February 13, 1950, Serial No. 144,007 f 15 Claims.

This vinvention relates-to pistons of the type operable within cylinders of internal combustion engines. f

In accordance with my invention, a unique vstructural combination is utilized for attaining superior lubrication'of the piston andipiston rings within a cylinder of an internal combustion engine, the principal'feature of such construction being the combination of'wick-type piston rings with ring-receiving recesses formed wthin'the piston skirt, advantageously in the lower portion thereof,` in communication with the interior of the piston. Constant absorption of oil by the piston rings and a wiping lubrication of the cylinder Walls duringoperation of the engine, together with oil retention by such piston rings during engine inactivity, insure thorough and proper lubrication at all times, including the critical' phase of engine starting. y

I have found, however, that with certain modern types of internal combustion engine pistons which are not'perfectly cylindrical, that is to say, pistons which are somewhat elliptical transverselyy of their lengths, difficulties are encountered with the relatively soft, wick-type piston rings. Such piston rings have a tendency to bulge into those clearances established between the piston and cylinder walls by reason of the mutually different curvatures thereof, leading to early'disintegration of the rings.

It is a specific object of the invention to correct this dimculty, and to thereby render the advantageous features of my invention applicable to internal combustion engine pistons which are somewhat elliptical transversely of their lengths.

Other specific objects are:

To` rmly contain a wick-type piston ring against `bulging during operation.

To accomplish the above, while providing for` free interflow of oil 'between the hollow interior and the exterior of the piston.

This is Aaccomplished by the provision of sloping ceiling-like inserts within and intermediate the length of the hollow piston above the wrist pin joinder.

Further objects and features of the invention 'y will be apparent from the following detailedV description of the several embodiments illustrated in the accompanying drawings to exemplify the piston along the long or principal axis of the ell liptical formation and at right angles to the short '1 axis;

Fig. 2, a vertical section correspondingl that' of Fig. 1, but taken along the short axis of the elliptical formation, that is to say, along the wristV pin axis of the piston;

Fig. 3, a partiallyl offset horizontal section taken along the line 3-3 of Fig. 1; l Y

Fig. 4, a similar section taken along the lineI 4-4 0f Fig. 1;

Fig. 5, a fragmentary vertical section taken lon K the line 5-5 of Fig. 4 and drawnvto a considerably enlarged scale;

ligI a plan lview of one'arciiate segment of the piston ring carrier, drawn to a scale between Y' that of Fig. 5 and the other figures;

Fig. 7, an inside elevation of such segment; Fig. 8, a fragmentary section taken on the line 8 8 of Fig. land drawn to a reduced scale;

Fig. 9, a vertical, axial section taken through a more general embodiment of theH invention,

' wherein the walls of the cylinder in which the In attaining these specific objects I 'provide a rigid'piston ring carrier, which istruly annular in formation and conforms exactly with the cylindrical bore of the cylinder within which the piston works. Such piston ring carrier erably made up of ispref-v a "plurality of arcuate segments, which fit within a piston-ring-receiving recess of the piston skirt. Further, the carrier is formed to provide adequate passage for'oil be-`V tween the piston ring proper and'oil-supply openings leading from the hollow interior ofthe piston. -v l Another specific object of tion is to prevent spray oil from reaching deeply into the hollow interior of the piston and into contact with excessively hot portions thereof when the conventional wrist pin joinder betweenl piston and connecting rod is employed, and to direct collection of such spray oil where it will be mosteffective in charging rings with lubricant.

piston is positioned are illustrated fragmentarily,

the piston being truly cylindrical in formation y and drawn to a scale somewhat enlarged'ove'r that of the preceding gures;

- Fig. 10, a view in'cmposite horizontal section, showing fragmentary transverse sections taken substantially on the'lines. Ill-l0 and lila-Illa,

respectively, in Fig. 9, the former appearing in the upper part of the view and the latter in the lowerpart; A

Figs'll, v12, and 13, fragmentary portionsr of Fig. 9,' illustrating different constructions of de` d tails;-

Fig. 14, an enlarged detail view, in plan, illustrating a fragment of a suitable form of wicktype piston ring; and

the present inven-r d the wick-type ypiston Fig. 15, an actionl diagram. Referring to the drawings:

Theiiiusiraied piston of Figs. 1 through sis of the type which is somewhat elliptical transversely of its length, as appears in Figs. 3 and 4. It is made up in general, as is customary, of a piston head i!) anda depending circumferential skirt'l l. `The hollow interior of the piston is open to splash lubrication from the lower open end of the skirt In accordance with the generic aspeotslof-"lmyf f invention a plurality of annular receiving recesses for piston rings are formed within ,the

against the inside anges which define the inner .channel 22m. thering carrier., exerting .outward- -m-ly directed2ipressure@'"thereagainst.; 'I'husV- such inner channel 22 is left free for the inter'low of oilbetween passages Il and 24, and, further, for the now of oil from the upper tier of passages I 'l '-downthrougn the lower tiers thereof. In order to prevent spray oil which enters the lhollow interior ofthe piston through the lower lowermost portion of the piston skirt 1I'. In the' lo 'open 'end oi the piston skirt Il, from penetrating illustrated instance, such receiving recesses-,1in@1 dicated Id, extend internally of the piston within an annular housing l5 formed as an integral" part of the piston skirt H. The inner Wall of such housing leprojects ,upwardly `al suitable .dis-z,L

tance,\iase-atfif5a, to provideaninternal, annular cup l-fwimmediately yabove thef'housing proper; forv the purpose of maintaining a reservoir offlubri-Le` catingqoill.; :l

The ring-receivingrecesses :I4-'aref advanta-'i geouslyrioonsiderably vdeeper-y consideredV radially of thegpiston; than they ar.e.wide,^considered ylon'-A gitudinally of thefpistonisliirt,` therebyT` providing.

extended bearing surfaces for the pistoni ring v 25 aboverland eXtendingtpara-llel with the .vristpin1 faxis, andtheloweriedgeslying above'theannular x -f Spray oil Whichf normally wouldy carriersf -i e The :rho-usingi'i'rg-A iseperforatedf'at" intervals: aroundfiitsg. fciireurnierential-:extent:YK byf small pasisageslHi whiclrextendl downwardly from fthebotrtom ofethef oil reservoir a lr6y 'through' theseries'iof v ring-receiving recesses: 4z .-Suchrp'assagesv are con-- veniently provided by drilling upwardly through* the several'transverse-webswleof the housing: The bottom setfof'passages'so'produced are then f '.f'i2!, nor through portionsof-the piston skirtzuf v pluggeoly-.a'sfat |:9..- Thus, sets of: openings` are'provided which establish oil-flow communication 'of Whereas in the instance of the more, gen-eral f2( As illustrated inf-Figs. Sfand 7',the ring carriers i are preferably mademp of a series of individual;

rigidrazicuat-e;segments-10, which areiassernbledi 50.,:p1ston rings 26 absorb a certaink amount of such y sprayffgoilidue .toatheirporous nature; and also act by a wall 23d Suchfavall ziispertorated; atiinf tervalsfaroundffits length "by means-of Voil-"now v30' ervoirfliiit' nzdeeplywintc therinterior-of the piston and from coming in Contact with the excessively hot under- "surface'ni'the'*piston head lo and adjoining excessively hot inner surfaces of the piston skirt, a

.'formed through opposing portions of the pistonff axis.zflhu .thezce .fa vaulteduoeilin'giaerosszfthe' entire' `hollow inv'I terior-foiithe piston; with'the: ridge line being i oil reservoir d6' each .f-deeply ntofthe 'hollen/interior of the piston #is defleotedibyrthe ceiling plates 28 into the res- It should/.be noted that, asiillustrated'y in kFigli, the slots 2.2 :.don-otl extend itimoughI the struts 35' ,not eiectia separatiomoi'yfther Lippen-portion Vofy the ring-receiving recesses y-l4fwith th'einteriorsoi? r the piston, and particularly with th oil'reservoiriM l B the pistoni'fromrithe lower-portion thereof.y A d In operation; is'plash :bil is; Ithrown :against the exposed r cylinder: walls'fonathe upstroke ofv the y 'piston-,f fand iswipeor=clea`r:byr thepiston ringe' 2 5 'L0 on the dovvnstroke -ofrthe pistoninSince the `piston'lsriirigszY arevr concentrated"in:v ythe* lowerrnost` portionziofitl'r'ei pistoni skirtfthey are out-ofthe zone of excessivefheat.i Also, they traversesubconventional 'practices --Furthermore'f since the -ffgas Wicks to distributefoilwfrom.the4 reservoir i6: against ff the" cylinder Walls; :a' f `thorough wiping 's `assured at allY passages 24, thereby enablingoib tofseep between the outerfand` inner :channels'i and 2-2;frespec' f tivelya fiilurther- (the .arcu ate inner 'fedges'fof "each a segmenti .2n-:are f-'notch'edf asratfZ 5; to providefor" interioiuonthe'fpiston,` byfway of passages* Ils" As laid end-to-end Within a receiving rece'ssil'4;1=:

such arcuate-segments:20i :form fa 'truly-.circular G5 the oylindenwal'lsz:

c The uppersiportion of` the` piston skirt is `prefy"series-y oii' annularfoil-retaining channels 30y whichaid: in'fzlubricatingther upper portion of sourcesfof`r lubrication;

An annularrecessionl about *the uppermost and Enttedfwpismn:Ring' Assembly for the 7*()4 portioirofthe piston, and the provision of a se- Pistonlfof 'Internal Combustion Engines.

The ring carriers (preferablylt snugly within the respective-' reoeiving-`reoesses |4,1 and are backed. lbyy respective resilient' expander rings .21,y In eachinstancethev expander'ring '21 bears.

ries of"smal1,'annular serrations 32.for anchor- .ing carbon'that tends t0. form thereat, are features' Whichfare preferably employedin addi- '....tion t`o (the uniqueucionstructionA aforedescribed.

5. .Such"'serrations 'advantageously `cox/erwan. an-

`Itjhis not' alwaysnecessary to provide'rzsuch channels' 3E!,'l.for the piston'rings f and oil lm provided thereby are the primary '125 pair nfice-iiingriplatesi are slidablyrpositioned' 2 within". :receiving r .slots :525;: Fig. 8; appropriately vskirt fini: lSuch .peiling -:plates 231 slope upwardly The retention ofrioilgzbyf the wick-type piston 11' aff-ringswa'nd by the: reservoir' I6l when-fthe engine is not operating isiirparticularly:important in Y ilow offoilfbetween the inner @channels 2:2 andthe" guarding rganstfscolingv 0f the Cylinder Walls" 6o upon startingrofnrthe engine;`

frorni'the;circumference'of thepi'ston'skirt to:a w f meetingfalonga centra/l" ridge linedying above the 'fbossesdlafiand abov and parallelrto the wrist :plates 28;form; in effect,

f' 'stantially no part ofrfthe cylinder. wal'ls'wl'iich` f iifvhavenot beeniactedrupon directly'by 'oil'spray This iszbontraryfto'thecondition'existingwhere pistonimingsrare concentrated in the uppermostf 'i i portixniroiatheA piston` skirtdnraccordance y'with nulus substantially equalin width to the 'thicknessofthepiston head I0, so that the anchored carbon soon builds up an'additional seal against oil creeping into the combustion chamber portion of the cylinder.

While this particular construction is particularly applicable to pistons which are somewhat eliptical transverselyto their lengths, it may be also applied to advantage in4 connection with 'trulycylindrical pistons.

A more general construction is, however, illustrated in Figs. 9 through 15, wherein no separate carriers arelemployed for the oil-absorbent or ditioned graphite filler, and reinforced by fine metallic wire or textile threads 63, if desired,

but are preferably constructed in accordance with the disclosure of my afore-referred-to patent application Serial No. 83,846. In this particular instance, .the piston rings are of an unusual cross-section, in that the dimension radially thereof (and therefore transversely of the cylinder) is appreciably greater than is customary in piston rings of conventional types. The purpose of this is to provide an ample transverseA bearing area in the respective grooves 44, so that the tendency of a ring to become loose in its housing 43 is practically eliminated. v

Furthermore, the extent of the transverse annular area of each ring housing is suflicient to accommodate a plurality of circumferentially spaced oil holes 41, disposed to provide passages for splash oil from rthe interiorof the piston to the piston ring, these holes being shown in this instanceas located in the upper walls of the channel 43. At the inner edge of each ring housing isa raised edge portion 48 that serves to define a depression or trough 49 which vfunctions asa miniature oil or lubricant reservoir. The outer circumference of the piston head 4l is somewhat smaller than the circumference of the main body of the piston, so as to provide ,l

clearance in a manner that is commonpractice.

As illustrated, this'piston assembly is arranged for use with the connecting rod assembly of my Patent ita-'2,513,023, granteduune 27, 19150, and' entitled Piston and Connecting Rod Assembly.

l Accordingly, the piston head 4| is constructed so i as tovaccommodate the cradle foundation plate `assembly 5l), which is connected to the piston head as by means of rivets 5I. n

The structural characteristics of the rings 45 are such that the ends thereof, asv at a, can be f tightly squeezed together, making it desirable that the rings initially are somewhat larger than the diameter of the cylinder. plete circumferential contact between the ring and the cylinder wall. In this connection it should be noted that these rings are porous and essentially similar to packing, Aand might be said to befmade up Yof packing material.

This assures com- In operation,` oil feeds from the `reservoir through holes 4'! directly onto a bearing area of the corresponding ring, and, because of the capillary properties of the wick-type or oil-absorbent ring structure, the oil reaches substantiallyevery part of the bearing areas.

It is to be observed that the expansion rings 46 serve not only to exert a radially expansive stress on the rings 45 to press them against the cylinder wall, but, considering that vsuch rings are flexible and somewhat resilient, although rm in structure, they also act to bulge the rings axially of the piston, thereby causing them to 'bear axially against the opposing tranverse faces of the channels in the housings 43. This is indicated in Fig. 15, where the arrows 51 indicate the force exerted by the expansion ring 46, and the arrows 58 and 59 the resulting forces acting against the channel faces 60 and 6I, brought about because of the yieldable property of the piston ring 45.

While the preferred cross-section of the ring is shown in Figs. 9, 11, and 12, Where the axial` dimension is considerably less than the transverse dimension, it is possible to secure excellent results even where the dimensions are reversed, as in Fig. 13.

In adapting the invention to engines of radial type and the like, where the reservoir trough of Fig. 9 could have no utility, the ring-receiving, annularly channeled housings are constructed as illustratedat52 in Figs. 12 and 13. There, oil holes 53, 54, and are spaced circumferentiallyof the channel, and extend through the upper, inner, and lower walls, respectively, of such housings, thereby making it possible for the oil that has splashed at random through the inside of the piston to reach every part of the piston ring 45, in'Fig. 12, and the piston ring 56,

rin Fig. 13.

The wick-type, oil-absorbent piston rings mentioned'hereinabove as being set forth in detail in my copending application Serial No. 83,846, are claimed per se in that application.

While Figs. 9 and 11 illustrate a construction wherein the ring-receiving, annular housings and the wick-type or oil-absorbent piston rings are distributed throughout the length of the piston skirt, I have found the arrangement exemplified by Figs. -1 and 2 to be definitely preferable in most instances, since the rings are thereby protected against' 'any excessive heat which may be present Aadjacent .the piston head.

The present application,as amended, constitutesa continuation-impart ofl my copending patent application Serial No. 5,450, filed January 30, 1948, and entitled Pistonfand Piston Ring Assembly, which latter application is being abandoned in favor of the present one.

Whereas-this invention is here illustrated and described with respect to particular preferred forms thereof, it should be understood that various changes may be vmade therein and various other forms may be rconstructed on the basis of the teachingy hereof, by those skilled in the art, without departing from the protective scope of the following claims.

I claim:

1. In a piston for internal combustion engines, said piston having a head and a circumferential depending skirt open at its lower end, a series of annular receiving recesses formed externally in the lowerrnost portion of the skirt adjacent the oplen end thlereof; piston ring carriers tted within the respective receiving recesses; relative- 'Y 8 ly Soit, avicltypepiston. ringsitted into respecfnA ringsrfpositicnedWithin .the respectivefring-re-r w tive pistenufng carriers; :resilient expander rings ceivingfrrecesses; :resilient expander.v'fringsrA back- A backing said .-.cai.iers-;a:and oil-'flow imassages .-ing said fpiston rings;.z:and voil;holesextendingv extendin through ftheopiston slirtand through -hrough the pistonsskirtfat:andv spaced circum-'= said scaliierszz-azand spaced ycircu-mfer;entia-llyf..s *.ferentially around said ring-receiving'-.iiecessea around said receivingi-recessesfuto'a:establishoila v1-so as=tofconcluct ysplash#foil""fnomfthe interior-'of flow 4:comniunicatimn rbetween `said spiston rings f. the pistonon-t'o said pistoniringsg: i and the: hollow interionofxthe piston, sonas-cto; 10. The contcbinationuecitedrinclainfi:9,whereinw-zA conduct Splash-oil irom'the'interiorfoffthefpistonwv.; :fthe pistonskirthas'its.lowernostzportionfformed onto fsaid piston: rings.'y ny.- lo asa housing which projects into the hollow'inte;.. s f

2. The combination recited Azin.clai1n,11, f-Wheree rior ofcthepistonsWhereinvtheuannularring-ra in theA ring carriersrare. made upof;-apluralitys ceivingV recesses extendwithinfsaid housing into i: of indivi-dual', arcuate segmentsf'.: registry with thefhollowfinterioriotthepiston; and

3. The combinationmecited'mfclaim'. 1, wheres-:ffii wherein the oil holes comprise-sets otperforae' in theipistonii's somewhat-elliptical'transrerselyiapticnszextending =throughiithe uppernvall of said -1 of itsniength, ,but theipistonifring carrier.iisrtrulycfn.,:housing*downithroughzthe several wehsr'between cylindrical;n indviduf'iliannularvreoesses:` c;

4. A :pistonrfor internal ycornlnlstionuengines; 11. The 'combinations'recitedin claim A10, comprising@J piston skirtyfa, pistonfhead zclosingflf; :.wherein ythe inner circumferential'wall '-:ofthe one end of ther'pistonwsloirt; a serieslotgannularto.:housingpprojectsfupwardly. to define, an `oil rc'- receiving recesses formed externally insaid pisa @taining sreservoz'u'-,l upon "the top Wall of thef'houston skirt adjacf-:ntthe said openzend thereofes.a-fy ing. f; plurality'zof:segmented .pistonri-ng carriers pi-ltteduA 12. The combinationrecitedin claiin iii, where-r into the respectivenreceiving,recesses; bachi ofzf in bored bosses pro-ject inwardly from opposite i said carriershaving an outerpistonfring-receiv- 251`v sidesffof the'.pistonskirt,,intermediate thelength ing channel fia-.nd an irnoeral oil-flow "chann'ek 3 thereof@ and above-the=housing;aswristpinfbea resilient expander rings backing teach .of Vsaid 'ingsyfafnd Whereinfa-vaultedceilingisfprovided ring carriers; relatively soit; ,'Wiclbtypeipistongf; acrossdhel entire"hollowl'interioriofusthe piston rings; tted...within,: the pistonering-receiving immediately above said bossesv channels of: the' respective carriers; and oil-flow .3o 13. The combination recitedin claimy 9,1wherepassagescspaced circumferentially 5 around `rsaid 1Min the'ring-receiving'recessesfof-.csaid pistonslrirt receivingy :recesses and establishing flow com-w are formed by respectiveannular"housingsiwhichi' municationfizbetween-=the said piston ringsE and .project inwardly: of the' `piston skirtz: and havev the hollow. interiorfotA the. piston,;scf as dio.: conraised,y circumferentialedge portions'. WithinY the duct zsplashfoil from `the interior ortho. piston'.35fpiston,.-forming,.reservoirs'rfor-the collectionof onto fsa-id pistonrings. a: sprayfoil, at least someo said oil:l'ioleslteimb 5. The combination recited in claim- La, 'Where-:f f nating-fwithin'vsaid reservoirs'oraconducting oil: in each `carrier Asegment `compriseszswan outen: to the-said piston rings:y piston-ring-receiving. channel, and anfinner cile; 14. Inzan internalrccmbustion engine .piston"ff. flow channel, the two channels being separated Jhaving awpistonheadiand skirt,the cornbin-atkm'wv by afwwall; @and Whereinvzthe oil-.flowmassag of a circumferential ring-receivingrecess.formed' meansA also include perforationsformedatspace externally vin'said ipistonuskirtpan oilfabsorbent l intervals through y.said useparating' wall, lfand pistoni ring positioned Within said ring-receivingl` notches-inthe defining rims yoi therinner. chanelV z recess;iaresilient expander ring backing said pis-- nel, 2 45 ton ring;4v and oil'holes extending through the 6. A piston ring, comprising an-annular,rigidi-.1` .'f pistoniaskirtwat l and spacedmcircuinferentially Y ring formed with ,ani external,- annular channel varound said ring-receiving recess,` so astovcon` and with an -internalf annular channel,the two l'.'ductasplash'ffoil fromi'the. interior/of the piston channels beingl .separated-.hva `Wall; a series of, onto said piston ring. openings extendingatspacedintervals-throng g: 15. The combination.recitediinclaimf14,fwherea-rf u and around said wallpa .seriesofopeningsfzexa in thering-receiving recess is denedfin' part by: tending :through-an internal channel-.dening an annular-housingrwhi'ch' protrudes intcthe holrim Wall; and airelativelysoft, wick-'type :pack low interiore-f the piston; and wherein-the upper 1:1'- f ing ring -ttedf` into said external.channelaflzf Wall of said hcusingis cupped asla reservoirior 7. The combinationr recited. in clai-mx; :Where-15530K said oil holes'leadingfinto said ring-ieceivng in the rigidring ismadeup of a plurality .of-imei recess'from said reservoir.'A :f dividual arcuate segmentss' 8. An internal combustion `enginepiston.and WILFRID HEUSSR" piston ring assembly, s comprising a -piston head;Y y, v a skirt depending from said head; :a plurality'zoi'e References-Gell the le'ofnfthls patent longitudinally spaced:y annularly; v channeled;` UNITED'STATES PATENTS l housings extending inwardly orf/said skira-the Number Y Name Date channels thereof being `opengexternally of the 1,092,834 l ,Haas Apr. 14., 1914 skirt;gporcus ringsotpacking material having 1 .i 1,251,906` f 1918 lubricantdiiusing properties substantially; 05 121353,30() 1913 throughout-.the structures: thereofapositioned 1,392,536. 1921 within the respective channels, and conduitsior,h 1,495,773 1924 a, lubricant leading from the interior of said skirt I 1,548,943 i 1925 directly` into said channels. 1,735,291 1929 9. The combination` with an internal combus- 70 1,743,023l Cal-tab Jan. 7; ,i930 tion enginepiston having apiston head and skirt 1,967,573 .1 FOX L July 24.,.1934 and a-plurality .of annular ring-receiving recesses ,1 2,15434,2vv .Marvin Apt 11., 1939 v f deinedfexternally ofsaid piston skirt in lspaced 2,396,018 Mis 21; Mai-.'55, 194.6 i i seriali-relationship longitudinally thereof, of a 2,464,710 Patterson Ma1 11'15,1949

corresponding #pluralityofoilabsorbent' piston 75 24466252 McFalL Apr. 5,1949 ma 

